In recent years, images are formed on a sheet using decolorable colorants which are decolorized if heated. The sheet, on which the images are formed using such decolorable colorants, can be reused by decolorizing the images by heating the sheet using a decolorizing apparatus.
The decolorizing apparatus includes first and second heating units configured to come into contact with one surface and the other surface of a sheet and heat the respective surfaces, and first and second heat source units configured to heat the first and second heating units. Here, in the modes of the decolorizing apparatus, it is considered that a double-surface decolorizing mode and a single-surface decolorizing mode are set. Here, in a case of the double-surface decolorizing mode, it is considered that both the surfaces of a sheet are decolorized using the first and second heating units while simultaneously heating both the first and second heating units.
On the other hand, in a case of the single-surface decolorizing mode, it is considered that the decolorizing target surface of the sheet is decolorized while heating only a heating unit which corresponds to the decolorizing target surface of the sheet. If so, the heating unit which corresponds to the non-decolorizing target surface of the sheet is not heated in the case of the single-surface decolorizing mode, and thus it is possible to save electric power as much as that.
However, in the decolorizing apparatus, it is necessary to enable a stable decolorizing process to be performed in addition to saving of an electric power.